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  1. Circadian rhythm - Wikipedia

    A circadian rhythm (/ sərˈkeɪdiən /), or circadian cycle, is a natural oscillation that repeats roughly every 24 hours. Circadian rhythms can refer to any process that originates within an organism …

  2. Circadian Rhythm: What It Is, How It Works & What Affects It

    Mar 15, 2024 · Your circadian rhythm is the pattern your body follows based on a 24-hour day — it’s the name given to your body’s internal clock. This rhythm tells your body when to sleep and …

  3. What Is Circadian Rhythm? - Sleep Foundation

    Jul 23, 2025 · Your circadian rhythm is your body’s internal clock, helping regulate sleep, wakefulness, hormone release, and other biological processes over a 24-hour cycle.

  4. Circadian Rhythms | National Institute of General Medical ...

    May 20, 2025 · Most living things have circadian rhythms, including animals, plants, and microorganisms. In humans, nearly every tissue and organ has its own circadian rhythm, and …

  5. Circadian Rhythm: What It Is, How it Works, and More - Healthline

    Jan 22, 2025 · Your circadian rhythm is your body’s internal clock. Light, sleep patterns, hormones, meals, and temperature can all influence your circadian rhythm, which in turn can …

  6. CIRCADIAN Definition & Meaning - Merriam-Webster

    Dec 5, 2016 · Most often, it's seen and heard in the term circadian rhythm, which refers to the inherent cycle of about 24 hours that appears to control various biological processes, such as …

  7. Circadian rhythm | Definition, Examples, & Facts | Britannica

    Nov 19, 2025 · circadian rhythm, the cyclical 24-hour period of human biological activity. Within the circadian (24-hour) cycle, a person usually sleeps approximately 8 hours and is awake 16. …

  8. The Biological Clock: How Circadian Rhythms Affect You

    Apr 21, 2025 · Circadian rhythms don’t just control sleep—they touch nearly every aspect of our physiology. The timing of hormone release, body temperature, digestion, immune function, …

  9. Circadian Rhythm: What Is It, How It Works, Why It?s ...

    Sep 2, 2025 · The circadian rhythm is 24 hours in the human body and is commonly referred to as the body ’s biological clock. One of the most essential and well-known circadian rhythms is the …

  10. What Is Circadian Rhythm? How It Works and Factors That Affect It

    Mar 10, 2025 · A circadian rhythm is the natural, internal clock that regulates the sleep-wake cycle and repeats roughly every 24 hours.